The present invention relates generally to systems and methods for airborne particle detection, and more particularly to system and method for detection of biological aerosol particles.
In the prior art, detection of biological aerosol particles typically comprises particle impingement on auger plates followed by examination of the plates by a trained mycologist or bacteriologist for determination of contamination levels. This procedure normally requires about two weeks for laboratory testing and is substantially affected by the type of auger used, growth media, time between sampling and analysis, storage/shipment conditions, and other factors. Measurement of total biological aerosol level requires several different augers to grow the various biological materials. The procedure has substantial variability in accuracy of analyses by the same laboratory on samples taken at the same location and time (typically up to 3 orders of magnitude in reported biological concentration), and, therefore, multiple samples are required to obtain statistically useful data.
The prior art systems for detecting biological aerosol particles measure flow of electrical current through an air sample, include sensitive electrometers to measure current, are slow and require a large concentration of biological particles per unit volume of sample, and are therefore not adequate for measuring low concentrations or any field environment monitoring.
The invention solves or substantially reduces in critical importance problems in the prior art as just stated by providing system and method for detection and concentration measurement of airborne biological aerosols, wherein a sample air flow is passed through a soft ultraviolet ionizing chamber and exposed to ionizing energies of less than about 7.5 eV. Charged biological particles in the flow are distinguishable from less readily chargeable non-biological particles. Biological aerosols are detectable discriminately as single particles in dusty environments.
The invention may be used for detecting spores, fungi, algae, pollen, bacteria, organic dusts and some viruses at single particle to high concentration levels, and finds particular utility for monitoring areas sensitive to airborne biological materials, such as clean rooms, surgical suites, hospitals and food preparation areas, or for detecting biological warfare agents. The invention provides the only known system and method for real time assessment of infectious biological aerosols such as legionella.
It is a principal object of the invention to provide system and method for detecting airborne biological particles.
It is a further object of the invention to provide real-time particle detection method and system for biological aerosols.
These and other objects of the invention will become apparent as a detailed description of representative embodiments proceeds.